Integrated parameter display

ABSTRACT

The integrated parameter display operates with a programmer and multiplexer to display an unlimited number of meters. The meter faces are provided on a film strip which are selectively projected onto a screen. The meter reading is superimposed on the selected meter face by a galvanometer in accordance with the value of a parameter being measured. The meter faces are placed on a film strip with a coded address adjacent thereto. The desired address is punched into a keyboard and compared with the film strip being driven until the selected address matches the address adjacent the meter face to be displayed.

United States Patent Blizard et al.

[ Feb. 19, 1974 [5 INTEGRATED PARAMETER DISPLAY 3,299,272 1/1967Furukawa 235 92 u O I 1 Robert Blimd; Christ 31131832 611323 X353;333233;?

Pederson, both of Littleton; John T. Polhemus Englewood an of ColoPrimary Examiner-Maynard R. Wilbur [73] Assignee: Martin-MariettaCorporation, New Assistant ExaminerRobert F. Gnuse York, NY. Attorney,Agent, or F irm-Sughrue, Rothwell, Mion, 22 Filed: Aug. 4, 1970 andMacpeak [21] Appl. No.: 60,953

Related US. Application Data 57 ABSTRACT [62] g i g gg 524911 1966 Theintegrated parameter display operates with a programmer and multiplexerto display an unlimited num- [52] U S Cl 235/61 7 R 250/219 FR 353/26ber of meters. The meter faces are provided on a film 235761 12 stripwhich are selectively projected onto a screen. [51] Int Cl 'G06k I015The meter reading is superimposed on the selected [58] Field 12 N 92 vmeter face by a galvanometer in accordance with the value of a parameterbeing measured. The meter faces 235/611 250/219 219 353/26 are placed ona film strip with a coded address adjacent thereto. The desired addressis punched into a [56] References Cited keyboard and compared with thefilm strip being UNITED STATES PATENTS driven until the selected addressmatches the address 221 1i adjacent the meter face to be displayed. e3,072,889 H1963 Willcox 250/219 D 16 Claims, 10 Drawing Figures TRANSFERPuLsE PROGRAMMER I MuLTI- PLEXER I DATA PULSES I I FROM sENsoRs ANALOGDIGITAL COMPUTER DATA sTREAM ADDREss PULSES ll/PULsEs l w L IIzrbgegsiisu DIGITAL SAMPLE AND L I DIGITAL To CONTROL I sELEcToR aADDRESS HOLD CIRCUIT ANALOG l PROCESSOR REGISTER COMPARATOR I F c2 IvERT R I I I T I I l KEYBOARD FILM READ I ADDRESS I REGISTER l I ICOMPARATOR as I I. I l x x l FILM DRIvE :1 I: :E I D PROJECTOR l L L lPATENTEUFEBIB m4 t 3.3193507 SHEU 3 BF 7 PATENTEDFEB 19 I974 A 3.793507SHEEI s or 7 FIG. 7

T0 KEYBOARD ADDRESS COMPARATOR 8 TO DIGITAL ADDRESS COMPARATOR FIG. 6

INTEGRATED PARAMETER DISPLAY This application is a division of Ser. No.524,911 filed 2/3/66 now US. Pat. No. 3,548,378.

This invention relates to a multiple meter display or integratedparameter display. More particularly, the invention relates to a devicefor displaying any one of a plurality of meter faces upon a viewingscreen.

As the aerospace technology becomes more sophisticated, it is necessaryfor the pilot of an aircraft or spacecraft to be provided with an everincreasing number of meter readings so that he can properly monitor thevarious functions of his vehicle. However, because of size and weightlimitations, the number of meters that can be included in such anaircraft or spaceship is limited. Also, the cost of such a large numberof meters may be prohibitive. With respect to ground equipment used insupport of aircraft and spacecraft, the number of meters needed may beeven greater than in the aircraft or spacecraft itself since it may bedesirable to monitor many additional functions of the craft which arenot essential for the pilots operation thereof, but are nevertheless ofsignificance. Again, such a large number of meters become almostprohibitive both from a space standpoint and from a cost standpoint.Thus, it can be seen that because of limitations of space, weight andcost, a new arrangement for meter display is clearly needed.

Among the objects of this invention are to provide a multiple meter orintegrated parameter display; to provide such a display in whichvirtually an unlimited number of meters may be displayed as required; toprovide such a display in which the meter faces are placed on a filmstrip for projection onto a screen; to provide such a display in whichany one of the meter faces may be displayed on the screen rapidly; toprovide such a display which may be connected to a conventionalprogrammer and multiplexer for sampling data; to provide such a displayin which a data stream address is compared with the address on thescreen of the display, and when they match, the data from themultiplexer is utilized to control a galvanometer which indicates on thescreen the value of the data being monitored; to provide such a displayin which the galvanometer is a mirror galvanometer which projects alight beam on the screen to give a visual indication of the value of thedata being monitored; to provide such a display in which the meter facedisplayed is chosen by punching an address into a keyboard addressselector and register; to provide such a display in which the addressfor each meter face is placed on the film strip next to each meter face;to provide such a display in which the selected address is compared withthe address for the meter face being displayed; to provide such adisplay in which film drive means is provided to cause a meter face tobe displayed whose address matches the selected address; to provide sucha meter display in which the address is placed on the film strip next tothe meter face; to provide such a display in which rapid updating ofeach meter reading may be provided; to provide such a meter in which theupdating interval may vary for each meter; to provide such a display inwhich additional meter faces may be added or removed from the filmstrip; to provide such a meter display in which either analog ordiscrete readings may be provided; and to provide such a meter displaywhich is fast and efficient in operation.

Additional objects and novel features will become apparent from thedescription which follows, taken in conjunction with the accompanyingdrawings, in which:

FIG. I, is a diagrammatic illustration of the elements which make up theintegrated parameter display of this invention showing theirinter-relationship with each other and with a conventional datamonitoring system;

FIG. 2, is a front elevation of the integrated parameter display of thisinvention;

FIG. 3, is an offset horizontal section taken along line 2-2 of FIG. 1to show some of the internal details of the integrated parameterdisplay;

FIG. 4, is a fragmentary front elevation on an enlarged scale, showingan alternative meter face for discrete readings;

FIG. 5, is a circuit diagram of a keyboard address selector and registerutilized in this invention;

FIG. 6, is an enlarged fragmentary elevation ofa portion of film stripshowing the address markings thereon and the manner in which theycooperate with the photo diodes to produce a signal indicative of thefilm position;

FIG. 7, is a circuit diagram of the film read register utilized inconjunction with this invention;

FIG. 8, is a partial circuit diagram of the keyboard address comparatorused in conjunction with this invention;

FIG. 9, is a truth table for explaining the operation of the circuit ofFIG. 8; and

FIG. It is a circuit diagram of the various motor control circuits.

In accordance with this invention, it is contemplated that themultimeter display system which may also be referred to as integratedparameter display system may be utilized with either airborne or groundequipment for aircraft, missiles and spacecraft for providing asubstantially instantaneous reading of any one of many thousands ofparameters being studied. As seen in FIG. 1, the conventional datagathering system comprises a programmer which sends signals into amultiplexer indicating which of the many sensors connected to-themultiplexer is desired to be read at a particular time. The multiplexerthen sends a signal from the particular sensor to be read to a computerwhich in turn transfers the information to a control processor. Thisinformation is stored in the control processor to be studied at a laterdate, as required. Although only one multiplexer is shown, it will beunderstood that the programmer may be connected to many multiplexerswhich in turn receive signals from many sensors, the total number ofsensors in a particular system may be many thousands. However, it can beseen that where an instantaneous reading of a particular parameter isdesired, it would be necessary to provide a separate meter for eachreading which is to be observed. Obviously, where several thousandsparameters are being measured, it is physically impossible to provide aseparate meter so that each of these parameters can be instantaneouslyobserved. Also, it will be very difficult for a person to observe such alarge number of meters even if this number could be provided. Theproblems are compounded with respect to airborne equipment because thesize, weight and expense of 'the equipment involved becomes prohibitive.

With the integrated parameter display D of this invention, the faces ofthe many thousands of meters to be read are placed on a film strip whichcan display any one of the faces on a screen within a short time period,such as two seconds or less. The data which provides the reading for themeter is periodically updated, as dis cussed below. As can be seen fromFIG. 1, the data stream address is fed into a digital address comparatordirectly from the programmer and the data pulses from the multiplexerare fed into a sample and hold circuit. The operator of the integratedparameter display punches an address such as a 4 digit octal number.into a keyboard address selector and register which in turn feeds thisinformation into a keyboard address comparator. The comparator comparesthe address fed into it with the address on the film adjacent the meterface being displayed on the screen as supplied by the film readregister. If these two addresses do not match, the film drive isactivated to drive the film to a position such that the correct meterface is projected onto the screen. A signal indicative of the particularmeter face being displayed on the screen is transmitted by the'film readregister to the digital address comparator which in turn feeds thecorrect information from the data stream address for that particularmeter displayed on the screen to the sample and hold circuit. The sampleand hold circuit then reads the'data from the data pulses supplied to itby the multiplexer which correspond with the meter face being displayedand this information in analog form is fed to a mirror galvanometerwhich projects a light'bar onto the image of the meter face on thescreen to' give a meter reading.

The multiplexer or other data source could supply digital datainformation in addition to or instead of analog data pulses. in thiscase, a digital to analog converter would be utilized in addition to orinstead of the sample and hold circuit, as shown in dotted lines in FIG.1.

As seen in FIG. 2 and 3, the integrated parameter display D may bemounted in a housing having sidewalls and 11, top and bottom walls 12and 13 and a rear wall 14. A front wall 15 has a viewing screen 16mounted therein provided with a row of are used lights 17 above andbelow the screen. These lights are used when a discrete reading isdesired as will be more fully described below in connection with FIG. 4.It will be understood that the lights 17 can be arranged in verticalrows along the sides of screen 16 rather than in hor izontal rows acrosstop and bottom, as desired. The number of lights may be varied asdescribed below, eight lights being shown for illustrative purposesonly.

Conveniently, a film strip 18 is mounted on a pair of spools 19 and 20which are mounted on spindles 21 and 22 attached to a diagonal wall 23which extends be tween front wall 15 and a front edge 24. The film 18 isfed through a film guide 25 mounted between the spools and directlybehind a'lens 26 but in front of a light 27 mounted in a housing 28 ondiagonal wall 23.

The particular meter to be read is selected by punching the film in onedirection or the other until thepropcr meter face image ispositionedzbetween the lightand the lens. in order to'provide adequatecoolingfor the housing a fan 35 is attached to motor '31.

The film image is projected through an opening 36 in front wall 1 5 tothe right of screen 16. The imageis reflected off a mirror 37 mounted onrear wall 14 onto.

odes will be activatedin response'to the'light transmitted through theaddress portion of the film so that a comparison may be'made between theaddress of the meter face being'displayed-with the address which hasbeen punched into the keyboard .29. Whenthe'filrn ad dress matches theaddress-punched on. the keyboard,

a the motor will be deenergized so that'theimage of the desired meterface will be projectedlon screen 16 for viewing. Convenientiy, thedigital address f40'may'be V placed on the meter face as shown in FIG. 2so that the operator may verify that he punched the correct admeterreading. a. a

For some indications, adiscrete reading is more .useful than an analogreading. For example, sometimes it is only necessary to know whether aparticular valve is open orclosed, a particular switch on or off, etc.In that case, the film strip may carry an image of the type vide a lightbar47 assho'wnin'FlG. 2 to indicate the h shownin FIG. 4 in which eightconditionsmay be read by observing lights 17. The number of discretereadings which may be placed on one meter face is limited only by thenumber of bits in eachdatazword from the data stream. A'meter face foran 8 bit data word has been shown for illustrative purposes.

The keyboard address selector. and register shown in FIG. 1 andpartially represented by keyboard 29 in FIG. 2 may be more fullyunderstood by reference to FIG. 5. The keyboard address selectorconverts a 4 digit octal address to a 12 bit binaryaddress and storesthis address in a 12 bit register. The eight switches numbered 0 to 7 onthe keyboard are connected to three OR gates 48, 49 and 50 which in turnare connected to three single-shot-circuits 51,52 and '53 respectively.Thus, when aukey is depressed, the digit is converted to a 3.bit binaryword and this word is directset into a 3 bit register. The wave pulsesgenerated by the single-shot-circuits S1, 52 and 53 are schematicallyshown thereon. in addition, three shift pulses are also generated eachtime a number on the keyboard is depressed to shift the 3 bit binaryword into the 12 bit storage register. Thus, a signal is transmittedthrough OR gate 54 tosingle-shot-circuit 55 which sends a signal, havingthe wave form shown, to OR gate 56 and to single-shot-circuit 57; Thesecond pulse is generated by a single-shot-circuit 57 which pulse issent to OR gate 56 and single-shot circuit 58. Finally,single-shotcircuit 58 generates a pulse which is fed into OR gate 56.The three pulses which are fed into OR gate 58 result in three shortpulses being generated by singleshot-circuit 59, as shown, resulting ina three digit shift of the 3 bit binary word from the 3 bit registerinto the l2 bit register. It will be noted from FIG. 5, that the pulseof single-shot-circuit 55 is longer than any of the pulses-fromsingle-shot-circuits 51, 52 and 53 so that no shift pulses will begenerated by single-shot-circuit 59 until the 3 bit binary word has beenset in the 3 bit register. The end of the pulse from single-shot-circuit55 initiates the shorter pulses of single-shot-circuits 59 and 57.Similarly, the end of the pulse from single-shotcircuit 57 initiates thepulses of single-shot-circuits 59 and 58. The end of the pulse ofsingle-shot-circuit 58 initiates the final pulse of single-shot-circuit59 to complete the shift from the 3 bit register to the 12 bit register.The pulse from single-shot-circuit 55'is fed through line. 60 to themotor stop control circuit for a purpose to be described in conjunctionwith FIG. 10.

It can be seen that it will take 4 octal numbers to fill the 12 bitbinary storage register. Thus, by depressing additional keyssequentially, the additional numbers may be fed into the register. Suchan arrangement provides for selection of up to 2,048 different addresseswith l 1 bits allowing the 12 bit to be used for the selection of adiscrete address. Alternatively, the l2 bit may be used for an analogaddress so that a selection of up to 4,096 different addresses may bemade. In this case, any of the meter faces may. be used for a pluralityof discrete readings, with the discrete lights 17 being switched on by a13th bit placed on the film address for that meter face which willswitch in a circuit controlled by a 13 photo diode 39 within housing 40.Of course, the galvanometer circuit would be switched out at the sametime. The discrete readings can be provided only when the multiplexer orother data source provides digital information to a digital to analogconverter, as shown in the dotted line portion of FIG. I, in order toprovide 8 discrete inputs. This operation will be more clearlyunderstood from the description of FIG. 6 below. If more than 4,096addresses are needed, it will be necessary to go to a 5 bit octaladdress and to use a larger shift register. Of course, all addressesneed not be used. The number of meter faces and addresses may beincreased by splicing them into the film strip or decreased by cuttingthem out of the film strip.

As shown in FIG. 6, each meter face on the film normally has associatedwithThe light a l2 bit binary code or address 61 plus a relatively shortstrobe or read bar 62 for determining when the l2 bit binary code shouldbe read and a centering bar 63 for centering the meter face on thescreen. Each light bar represents a binary I and each black barrepresents a binary 0. The small dotted circles under the addressrepresent the position of the photo diodes 38 with respect to the imageprojected upon screen 16. If desired, address 61 could be provided witha 13th bitfor discrete readings as discussed above. Also, strobe diode64 and centering diodes 65 are located as shown relative to theprojected image. The strobe bar 62 is made somewhat narrower than thebars of code 61 so that the addresses will not be read while the filmstripis between positions. The light portion of centering bar 63 isshorter than the dark portion so that it is not possible for the twocentering diodes to straddle a dark portion indicating that the film iscentered when it is not.

From the film read circuit'of FIG. 7, it can be seen that strobe diode64, through amplifiers 66 and 67, will enable the. AND address gates,such as AND gates 68 and 69, to allow the address reading from theaddress diodes 38 to be transferred via amplifier 70 and AND gates 68and 69 into the address register as represented by AND gates 71 and 72However, when a different address is punched into the keyboard 29, asthe film 18 begins to move toward the new address the strobe diode 64will be deactivated before the address photo diodes 38 thereby disablingthe address AND gates 68 and 69 so that the last address is held in theregister represented by AND gates 71 and 72 until strobe diode 64 isactivated by a new address. Thus, when the light hits the strobe diode64, it becomes a low resistance and supplies current to a high gainamplifier 67. The signal is inverted by amplifier 67 and provides binaryI or high signal to the AND gates 68 and 69 as well as other AND gateswhich are associated with the other photo diodes (not shown). When theinput to these AND gates from the strobe diode 38 is a binary l thecross coupled AND gate flip-flop register 71, 72 is set. On the otherhand, if a binary 0 or low signal is received from photo diode 38, theregister will not be set. In this manner, it can be seen that theregister for each of the photo diodes 38 will be set or not set,depending on whether binary 0 or a binary I is seen by the photo diodes38 as they read the address 61 on film strip 18. However, when anotheraddress has been punched in the keyboard 29 causing the film strip tomove to another meter face, a dark strip will move across the strobediode 64 so that it sees a binary 0, and the reading in register 71, 72will remain there until another binary 1 is seen by the strobe diode. Ofcourse, the information stored in the film read register of FIG. 1 willthen be transferred to the keyboard address comparator of FIG. 8, asindicated in FIG. 1.

The keyboard address comparator of FIG. 8 compares the address in thekeyboard register of FIG. 1 to the address in the film register andprovides the signal inputs to the motor control circuit of FIG. 10 todrive the motor, and hence the film, in one direction or the other. FromFIG. 8, it can be seen that each stage of the keyboard addresscomparator consists of two AND gates such as AND gates 73 and 74. Theinput from the keyboard register is represented as Q and Q and the inputfrom the film read register is represented as F and F. The AND gates 73and 74 are connected to an inhibit gate, such as OR gate 75 and inverter76, as shown. Thus, the comparison is made of the most significant bitfirst and if Q does not equal F then the remaining comparators areinhibited. Referring to the truth table of FIG. 9, it can be seen thatif Q and F are each a binary 1 then the output signal from AND gate 73is low, a low input is provided to OR gate 77 which is connected throughline 78 to the motor control circuit 79 of FIG. 10 to drive the motor 31and the film 18 in one direction. On the other hand, if F and Q are eacha binary I, then the output of AND gate 74 is low providing a low inputto OR gate 80, connected by line 81 to motor control circuit 79 causingthe motor and film to be driven in the other direction. Also, if theoutput from either AND gate 73 or AND gate 74 is low, then the outputfrom inverter 76 will be low which will inhibit AND gates 82 and 83ofthe next comparator When the two inputs F and Q are the same, i.e.,ei-.

ther a binary or a binary l, the output of AND gates 73 and 74 will bothbe high so that no signal is sent to OR gates 77 or 80 to initiate themotor drive. Also, the next comparator stage will be enabled through ANDgate 75 and inverter 76 and a comparison as described above will bemade. This process will continue down the line through'each bitcomparison until all bits have been compared. When the last bit iscompared the centering control gates are enabled and the'left-right'si'gnals are'furnished by the centering'pho'to diodes 65until both diodes are in centering bar 63 of FIG. 6.

Photo diodes 65 provide signals through inverters 86 and 87 to flip-flopcircuit comprising AND gates 88 and 89 as shown. The output from ANDgates 88 and 89 is supplied to OR gates 77 and 80 to control themovement of the motor during centering and to OR gate 90 which isconnected by line'9l the motor control circuit 79 of FIG. as shown, tocontrol the motor speed by conventional means (not shown) which are partof the motor control circuit 79.

The various motor control circuits are clearly shown in FIG. 10 whichare provided here for stopping the motorwhen a wrong address is punchedinto the keyboard or the end of the film is reached and for starting themotor when the select switch is closed, as well as means to prevent themotor from running until the complete address has been punchedintokeyboard 29.

If an invalid address is punched into the keyboard, i.e., an addresswhich is between two valid addresses, in a situation where all possibleaddresses are not in use, the motor drive circuit would continuereversing back and forth between the two valid addresses trying to findthe one that is missing. To prevent this continued reversal, thereversing signal is fed through an OR gate 92 into a 3 hit countercomprising flip-flops 93, 94 and 95 which are interconnected, as shown,and are connected to the motor control circuit 79. The number ofreversals necessary to stop the motor is arbitrary. However, in thecircuit shown, when seven reversals have been made, the flip-flopcircuits all contain a binary l which satisfy the three input AND gate96 clearing the motor start flip-flop which includes two AND gates 97and 98 thereby stopping the motor by breaking the circuit between theselect switch and motor control circuit 79. Also, the output of AND gate96 is connected through a flip-flop, which includes AND gates 99 and100, and AND gate 101 to OR gate'l02,

which is connected to the base of transistor 103 and completes thecircuit to a no-valid-address light 104 which is turned on so that theoperator realizes that he has punched an incorrect address. The otherinput to AND gate 101 is supplied through line 91 from the centeringcircuit.

To prevent the film from running off the spools l9 and at either end, asection of film is provided atone affect the accuracy of the readingssince the" scale is placed at right angles to the length of the filmstrip, as

end with an addressin which .eachof the 12 bits is abinary l and theother end is provided with an address in which each of the 12 bits is abinary O. A group of these addresses are put on each end of the film andread by two AND gates. For example,'AND gate 105 may be provided for thebinary 1 end of the film and AND gate 106 may be provided for the binary0 end ofthe film. Each gate is provided with 12 inputs, one for eachbiton the film address. If the film drive is driven beyond the normaladdresses, one of these gates will be satisfied,.clearin.g flip-fiopDZ.98 to stop..themotor; It will be noted that both AND gates 105 and 106are also connected into OR 'gate I02 so that the no-validaddress light105 will be lit up. e

In addition, it is desirable to prevent them'otor from running while anaddress is being punched into the keyboard 29. To prevent this, theflip-flop circuit 97,

98 is cleared by the first pulse through line 60 from the 8 shift ORgate 54 of .FIG, 5. This'disables the motor drive circuit. After thecomplete address has been. punched in, the s'elect keyis depressedto'rese't flip-flop 97, 98 and allow the motor to run so that thecorrect address may be found and the proper meter. facedisplayed onscreen 16. r

For high operation speed, the motor maybe driven at different speeds inorder to reach the desired address in the minimum amount of time. Thecircuitry for this 7 is not illustrated, but it will be understood thatafter the motor control cricuit 79. At the same time, a flip-flop withincircuit 79 is cleared, causing the motor to go to medium speed inreverse. The film is now driven at medium speed hack to the correctaddress and then at slow speed until the meter faceis centered bycentering diodes 65. However, small errors in centering will not ple andholdcircuit and all of the address bits coming in from the data streamaddressare identical, bit for bit,

to the address in-the film read register, as comparedby the digitaladdress comparator, a flip-flop (not shown) will be set in the sampleand hold circuit to allow a data sample from the data'pulses to be readinto the sample and hold circuit. .When the next transfer'pulse arrivesthe flip-flop will be cleared, disconnecting the data pulses from thesample and hold circuit. The previous data sample, however, will be heldin the sample and hold circuit, and updated as described below, until adifferent address has been punched int'o the'keyboard. The bit by bitcomparison within the digital address comparator is made by a set ofexclusive OR gates (not shown), one gate being provided for each bit.The output of all the exclusive OR gates are fed into an AND gate withinthe sample and hold circuit along with the transfer pulse from theprogrammer. if the output of all of the exclusive OR gates is high whenthe transfer pulse occurs, the flip-flop in the sample and hold circuitwill be set. If any one of the outputs is low, then the addresses do notmatch and the-flip-flop is not set. The sample and hold circuit alwaysholds the last reading or data sample it has received and provides asignal to mirror galvanometer 44 which causes it to rotate an amountproportional to this data sample to project a light beam 46 onto screen16, as described above, giving a reading for the particular meter facebeing displayed on the screen.

Advantageously, the meter reading being displayed will be updatedcontinually until a different address is punched into the keyboard.Every time the data stream address matches the selected address, thesample and hold circuit will read and store the data sample from thedata pulses and update the meter reading. The more critical parametersmay be sampled as often as 400 times per second, for instance, whereasthe less critical parameters may be sampled only two times per second orso. The frequency of sampling is built into the programmer.

From the foregoing, it can be seen that the novel objects and featuresof this invention have been fulfilled to a marked degree. An integratedparameter display has been provided for operation with a conventionalprogrammer and multiplexer in which a virtually unlimited number ofmeters may be displayed by placing the meter faces on a film strip forprojection onto a screen. The meter reading is obtained by utilizing agalvanometer for projecting an image onto a screen to give a visualindication of the value of the parameter being measured. The meter facesare placed on a film strip with a coded address adjacent thereto. Thedesired address is punched into a keyboard and compared with the filmaddress, the film strip being driven until the selected address matchesthe address adjacent the displayed meter. The film strip can be movedrapidly to change the meter faces, means being provided to assure thatthe wrong meter face is'not displayed, whereby the address number isplaced on the meter face so that the operator can tell whether or notthe meter face being displayed is the one he intended. In addition,means is provided for updating each meter reading at preselectedintervals and this interval may vary for the particular parameter beingmonitored. Conveniently, additional meter faces may be added to the filmstrip or meter faces may be taken off the film strip as required.Furthermore, the readings may be given in either analog or discretereadings.

Although a preferred form of this invention has been illustrated anddescribed, it will be understood that various changes and variations maybe made, all without departing from the scope of this invention. Forexample, in place of the mirror galvanometer, a galvanometer having apointer may be used wherein an image of the pointer is projected ontothe meter face image on the screen.

' What is claimed is:

l. A film strip for use with an integrated parameter display including aviewing screen adapted to display said film strip including:

a plurality of different graphic illustrations on said film stripadapted to be displayed individually on said screen;

a coded strip adjacent said graphic illustrations including a pluralityof differentiable indicia representing different binary addresses foreach graphic illustration, adapted to be read by sensing means in saidintegrated parameter display which causes a selected graphicillustration to be nominally positioned before the viewing screen; and

alternating differentiable centering indica, one said indicia beingshorter than the other indicia so that said graphic illustration iscentered with respect to the viewing screen when a pair of spacedcentering sensing means are positioned within said one of said indicia.

2. A film strip, as set forth in claim 1, wherein said graphicillustrations are placed at right angles to the length of the filmstrip.

3. A film strip as set forth in claim 1 further including differentiableread command indicia for causing said parameter display to read theindicia representing a binary address when said address indicia isproperly aligned with address indicia sensing means.

4. A film strip as set forth in claim 3 wherein said differentiableindicia representing binary addresses and centering and read commandinformation comprise a plurality ofareas each of said areas havingeither a first or second light transmissible characteristic.

5. A film strip as set forth in claim 4 wherein the shorter of saidcentering indicia corresponds to areas having the first transmissiblecharacteristic while the remaining centering indicia comprises areashaving the second transmissibility characteristic, said differentiablecentering indicia being positioned serially along the length of thefilm, said areas having the first transmissibility characteristic beingpositioned completely within boundaries defined as the colinearextension of the boundaries of said graphic illustrations transverse tothe length of the film, each of said centering indicia areas having thesecond transmissibility characteristic overlapping a defined boundary.

6. A film strip as set forth in claim 5 wherein the address'representingindicia associated with each graphic illustration is completelycontained within the defined boundaries associated with said graphicillustration.

7. A film strip as set forth in claim 6 wherein said differentiable readcommand indicia are positioned serially along the length of the film, aread command indicia area having the first transmissibilitycharacteristic being associated with each graphic illustration and beingcontained within said defined boundaries associated with said graphicillustration, read command indicia areas having the second lighttransmissibility characteristic being located alternately with respectto the read command indicia areas having first transmissibilitycharacteristics and overlapping a defined boundary.

8. A film strip as set forthin claim 1 wherein said graphicillustrations are meter faces.

9. In a data record positioning system for use in a data record displaysystem including a viewing screen, said data record being in the form ofa movable film strip containing a plurality of graphic illustrations, acoded strip adjacent each graphic illustration including a plurality ofdifferentiable indicia representing a different binary address for eachgraphic illustration, said positioning system including control meansresponsive to the address indicia and a comparison address code in anaddress selector register for moving the film strip to a predeterminedposition whereby a selected graphic illustration is nominally before theviewing screen, wherein the improvement comprises:

alternating differentiable centering indicia associated with eachgraphic illustration, and

first and second spaced centering sensing means, p-

erable in response to said centering indicia,

said control means including means responsive to .said centering sensingmeans for centering a graphic illustration with respect to the viewingscreen after the film strip has moved to a predetermined position.

10. The positioning system of claim 9 wherein said control meansincludes means for producing a signal indicating that the film strip isat the predetermined po sition, said centering means includes bistablecircuit means, enabled by said signal, for generating first or seconddirection signals in response to the state of said centering sensingmeans, and means responsive to said direction signals for moving saidfilm strip in a first or second direction whereby the film strip iscentered.

11. The positioning system of claim 10 wherein said differentiableindicia representing centering information comprises areas of first andsecond light transmissibility characteristics, said centering sensingmeans comprises photosensitive elements, centering, of a graphicillustration being effected when the first and second photoresponsiveelements simultaneously receive light from the area having the firsttransmissibility ator means for comparing saidread address code indiciaand said comparison code. and for generating said signal indicating thatthe film strip is at the predetermined location when said-read addresscode and comparison code correspond. r

13. The positioning system of claim 9 wherein said control means furtherincludes means, responsive to the address indicia and the comparisoncode when there is a lack. of correspondence therebetween, for causingsaid film to movein the direction of the graphic illustrationcorresponding to said comparison address.

14. The positioning system of claim 13 whereinsaid means for causingfilm movement in the direction of the comparison address iricludes logicmeans, responsive to the most significant digit of the address indiciaand comparison address at which non-correspondence.

exists, for producing direction signals, said control circuit furtherincluding motor-direction control circuitry responsive to said directionsignals.

15. The positioning system of claim 14 whrein said control circuitincludes means for indicating when an invalid address is supplied tosaid address selector register, said invalid address means comprisingcounter means for producing a motor disable signal in response 16.Thepositioning system of claim 9 wherein'said,

film includes analog to digital switching indicia, said control meansfurther including means responsive to the switching indicia forswitching the system to a discrete reading mode of operation.

1. A film strip for use with an integrated parameter display including aviewing screen adapted to display said film strip including: a pluralityof different graphic illustrations on said film strip adapted to bedisplayed individually on said screen; a coded strip adjacent saidgraphic illustrations including a plurality of differentiable indiciarepresenting different binary addresses for each graphic illustration,adapted to be read by sensing means in said integrated parameter displaywhich causes a selected graphic illustration to be nominally positionedbefore the viewing screen; and alternating differentiable centeringindicia, one said indicia being shorter than the other indicia so thatsaid graphic illustration is centered with respect to the viewing screenwhen a pair of spaced centering sensing means are positioned within saidone of said indicia.
 2. A film strip, as set forth in claim 1, whereinsaid graphic illustrations are placed at right angles to the length ofthe film strip.
 3. A film strip as set forth in claim 1 furtherincluding differentiable read command indicia for causing said parameterdisplay to read the indicia representing a binary address when saidaddress indicia is properly aligned with address indicia sensing means.4. A film strip as set forth in claim 3 wherein said differentiableindicia representing binary addresses and centering and read commandinformation comprise a plurality of areas each of said areas havingeither a first or second light transmissible characteristic.
 5. A filmstrip as set forth in claim 4 wherein the shorter of said centeringindicia corresponds to areas having the first transmissiblecharacteristic while the remaining centering indicia comprises areashaving the second transmissibility characteristic, said differentiablecentering indicia being positioned serially along the length of thefilm, said areas having the first transmissibility characteristic beingpositioned completely within boundaries defined as the colinearextension of the boundaries of said graphic illustrations transverse tothe length of the film, each of said centering indicia areas having thesecond transmissibility characteristic overlapping a defined boundary.6. A film strip as set forth in claim 5 wherein the address representingindicia associated with each graphic illustration is completelycontained within the defined boundaries associated with said graphicillustration.
 7. A film strip as set forth in claim 6 wherein saiddifferentiable read command indicia are positioned serially along thelength of the film, a read command indicia area having the firsttransmissibility characteristic being associated with each graphicillustration and being contained within said defined boundariesassociated with said graphic illustration, read command indicia areashaving the second light transmissibility characteristic being locatedalternaTely with respect to the read command indicia areas having firsttransmissibility characteristics and overlapping a defined boundary. 8.A film strip as set forth in claim 1 wherein said graphic illustrationsare meter faces.
 9. In a data record positioning system for use in adata record display system including a viewing screen, said data recordbeing in the form of a movable film strip containing a plurality ofgraphic illustrations, a coded strip adjacent each graphic illustrationincluding a plurality of differentiable indicia representing a differentbinary address for each graphic illustration, said positioning systemincluding control means responsive to the address indicia and acomparison address code in an address selector register for moving thefilm strip to a predetermined position whereby a selected graphicillustration is nominally before the viewing screen, wherein theimprovement comprises: alternating differentiable centering indiciaassociated with each graphic illustration, and first and second spacedcentering sensing means, operable in response to said centering indicia,said control means including means responsive to said centering sensingmeans for centering a graphic illustration with respect to the viewingscreen after the film strip has moved to a predetermined position. 10.The positioning system of claim 9 wherein said control means includesmeans for producing a signal indicating that the film strip is at thepredetermined position, said centering means includes bistable circuitmeans, enabled by said signal, for generating first or second directionsignals in response to the state of said centering sensing means, andmeans responsive to said direction signals for moving said film strip ina first or second direction whereby the film strip is centered.
 11. Thepositioning system of claim 10 wherein said differentiable indiciarepresenting centering information comprises areas of first and secondlight transmissibility characteristics, said centering sensing meanscomprises photosensitive elements, centering of a graphic illustrationbeing effected when the first and second photoresponsive elementssimultaneously receive light from the area having the firsttransmissibility characteristic of the centering indicia associated withthe graphic illustration.
 12. The positioning system of claim 11 whereinsaid film strip further includes differentiable read command indiciaassociated with each graphic illustration for causing said control meansto read the indicia representing a binary address, and further includingcomparator means for comparing said read address code indicia and saidcomparison code and for generating said signal indicating that the filmstrip is at the predetermined location when said read address code andcomparison code correspond.
 13. The positioning system of claim 9wherein said control means further includes means, responsive to theaddress indicia and the comparison code when there is a lack ofcorrespondence therebetween, for causing said film to move in thedirection of the graphic illustration corresponding to said comparisonaddress.
 14. The positioning system of claim 13 wherein said means forcausing film movement in the direction of the comparison addressincludes logic means, responsive to the most significant digit of theaddress indicia and comparison address at which non-correspondenceexists, for producing direction signals, said control circuit furtherincluding motor direction control circuitry responsive to said directionsignals.
 15. The positioning system of claim 14 whrein said controlcircuit includes means for indicating when an invalid address issupplied to said address selector register, said invalid address meanscomprising counter means for producing a motor disable signal inresponse to receiving a predetermined number of said direction signalsand lamp means, responsive to the disable signal for indicating to theoperator that an invalid address has been supPlied to the addressselector register.
 16. The positioning system of claim 9 wherein saidfilm includes analog to digital switching indicia, said control meansfurther including means responsive to the switching indicia forswitching the system to a discrete reading mode of operation.